Do filters have a real or practical limit? I've got hundreds of contacts.
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Al E.May 14 '12 at 17:56

I've found vague answers indicating ~1500 characters. You may have to perform multiple filters. For example, filter out your closest friends and put the mail into a different folder, then take out mailing lists, etc.
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AmpersandMay 14 '12 at 18:31